21801339663 has 8 divisors (see below), whose sum is σ = 29368128048. Its totient is φ = 14384388864.

The previous prime is 21801339601. The next prime is 21801339673. The reversal of 21801339663 is 36693310812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21801339663 - 2⁹ = 21801339151 is a prime.

It is a super-2 number, since 2×21801339663² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21801339673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37459056 + ... + 37459637.

It is an arithmetic number, because the mean of its divisors is an integer number (3671016006).

Almost surely, 2^21801339663 is an apocalyptic number.

21801339663 is a deficient number, since it is larger than the sum of its proper divisors (7566788385).

21801339663 is an equidigital number, since it uses as much as digits as its factorization.

21801339663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74918793.

The product of its (nonzero) digits is 139968, while the sum is 42.

The spelling of 21801339663 in words is "twenty-one billion, eight hundred one million, three hundred thirty-nine thousand, six hundred sixty-three".